FOREWORD

The overall goal of the Federal Highway Administration’s (FHWA) Visibility Research Program is to enhance the safety of road users through near-term improvements of the visibility on and along the roadway. The program also promotes the advancement of new practices and technologies to improve visibility on a cost-effective basis.

The following document provides an overview of the series of studies conducted under Phase II of the Enhanced Night Visibility (ENV) project and the development of the Phase III experimental plan. The ENV project provided a comprehensive evaluation of evolving and proposed headlamp technologies in various weather conditions. The individual studies within the overall project are documented in an 18-volume series of FHWA reports, of which this is Volume XII. It is anticipated that the reader will select those volumes that provide information of specific interest.

This report will be of interest to headlamp designers, automobile manufacturers and consumers, third-party headlamp manufacturers, human factors engineers, and people involved in headlamp and roadway specifications.

Michael F. TrentacosteDirector, Office of Safety Research and Development

Notice

This document is disseminated under the sponsorship of the
U.S. Department of Transportation in the interest of information exchange. The
U.S. Government assumes no liability for the use of the information contained in this document.

The
U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers' names appear in this report only because they are considered essential to the objective of the document.

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Technical Report Documentation Page

1. Report No.FHWA-HRT-04-143

2. Government Accession No.

3. Recipient’s Catalog No.

4. Title and SubtitleEnhanced Night Visibility Series, Volume XII:
Overview of Phase II and Development of Phase III Experimental Plan

16. Abstract
This volume provides an overview of the six studies that compose Phase II of the Enhanced Night Visibility project and the experimental plan for its third and final portion, Phase III. The Phase II studies evaluated up to 12 vision enhancement systems in terms of drivers’ ability to detect and recognize objects, visibility of pavement markings, and discomfort caused by glare from oncoming headlamps. Drivers’ ability to detect and recognize objects was assessed in clear, rain, fog, and snow conditions. The results indicated that supplemental ultraviolet headlamps do not provide sufficient benefit to justify further testing. The performance of supplemental infrared (IR) vision enhancement systems, on the other hand, was robust enough to suggest further investigation. As a result, additional IR testing, disability glare testing, and off-axis object detection on the Virginia Smart Road were proposed as a replacement for public road Phase III testing with UV–A. The details of the experimental plan for each of these testing areas are provided in the Phase III portion of this report.

ENHANCED NIGHT VISIBILITY PROJECT REPORT SERIES

This volume is the 12th of 18 volumes in this research report series. Each volume is a different study or summary, and any reference to a report volume in this series will be referenced in the text as “ENV Volume I,” “ENV Volume II,” and so forth. A list of the report volumes follows:

Volume

Title

Report Number

I

Enhanced Night Visibility Series: Executive Summary

FHWA-HRT-04-132

II

Enhanced Night Visibility Series: Overview of Phase I and Development of Phase II Experimental Plan